Recent anthrax threats to Homeland Defense demand new vaccine technologies. Problems with the current licensed anthrax vaccine include variable immune response, adverse reactions and high production costs. In addition, significant uncertainties exist regarding the efficacy for inhalation anthrax and the schedule and route of administration are suboptimal. The proposed work targets the development of a low-cost, safe and effective, non-invasive anthrax vaccine based on the plant transient gene delivery vector (TGDV) platform. This proposal tests the hypothesis that TGDVs can be used as particulate carriers of selected antigenic peptides derived from anthrax Protective Antigen (PA). The Dow team proposes that TGDV-based vaccines can be produced in plant tissues in large volumes and shorter time at significantly lower cost and minimal capital investment. The team further proposes that TGDVs can be formulated for non-invasive administration and due to their particulate nature provide enhanced protective immunity while minimizing side effects without the need for an adjuvant. Three different TGDVs that accommodate varying sizes of target peptides and assemble into different particulate shapes will be used to express four different regions derived from the PA. The constructs will be propagated in plants and used for immunology studies. The specific aims of this proposal are (1) engineering and cloning of antigenic determinants from the anthrax PA into expression vectors; (2) optimizing, producing and purifying recombinant TGDV's fused with target peptides, (3) testing immunogenicity in vitro using dendritic cell assays; (4) testing immunogenicity of selected constructs in vivo using nonhuman primates; and (5) conducting challenge studies in nonhuman primates. The new strategic partnership among The Dow Chemical Company (Dow), the Frauhofer U.S.A. Center for Molecular Biotechnology, The University of Maryland, and Ohio State University (Consultant) leverages expertise in manufacturing excellence, virology, immunology, and anthrax pathogenicity respectively. The partnership, in collaboration with NIH scientists offers advancement of this novel technology platform and ultimate commercialization of new vaccines of public health importance. [unreadable] [unreadable]